Fixes#8788
- Fixed missing argument lists on constructors, and improved handling for various cases of partially applied functions.
- Extended tests to check for correct `self` argument placeholders.
- Additionally reworked some questionable test code to maintain separation between server and client code.
<img width="1241" alt="image" src="https://github.com/enso-org/enso/assets/919491/5377f57f-18f0-4a50-a8ab-9331862ca547">
